1. Field of the Invention
The present invention relates to a reinforcing structure of rear pillars of a vehicle such as a motor vehicle, the rear pillars having mounted on each upper portion thereof an anchor bolt for a seat belt.
2. Description of the Related Art
In case an anchor bolt is mounted on an upper portion of a rear pillar, the following arrangement is conventionally employed. Namely, an anchor reinforcing member (i.e., a reinforcing member for attaching thereto an anchor bolt) is mounted on an inner member of the rear pillar, and a nut is fixed to the anchor reinforcing member to thereby fasten the anchor bolt thereto.
Further, in case a tailgate is provided in a rear portion of a motor vehicle body, the following arrangement is conventionally employed. Namely, hinge reinforcing members (i.e., reinforcing members for attaching thereto hinges) are provided on a rear roof rail, and hinges for the tail gate are attached to the hinge reinforcing members. The anchor reinforcing member and the hinge reinforcing members are independently or separately provided.
In the above-described conventional arrangements, the rear pillar is only partially reinforced by the anchor reinforcing member at a portion in which the anchor bolt is mounted. In order to improve the supporting rigidity of the anchor bolt, the rigidity of the rear pillar itself must also be increased. Therefore, the plate thicknesses of the inner member and an outer member of the rear pillar must be increased, resulting in an increase in weight.
In addition, in increasing the rigidity of the motor vehicle body, the connecting or combining strength between the rear pillar and the rear roof rail becomes an important factor. Conventionally, the combining strength between the rear pillar and the rear roof rail is improved either by increasing the plate thicknesses of the rear roof rail and a rear pillar inner member that is connected to, or combined with, the rear roof rail or by providing a reinforcing member that is combined to bridge the rear roof rail and the rear pillar inner member. This arrangement has, however, a disadvantage in that the weight increases or that the steps of assembling the motor vehicle body increase.
In view of the above-described disadvantages, the present invention has an object of providing a reinforcing structure in which the supporting rigidity of the anchor bolt can be improved without increasing the rigidity of the rear pillar itself, and in which the combining strength between the rear pillar and the rear roof rail can be improved without using a reinforcing member that is prepared exclusively for that purpose.